Method of producing lead hydrate.



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rmon'onn o. TIMIBY, or CHICAGO, ILLINOT-S.

METHOD 0F PRODUCING LEAD HYDRATE.

such as bars or cakes, as the anode of an elcctrolytic cell containing a' suitable electrolytc dissolved in water, such for example as a. neutral solution of sodium nitrate in water. 1 can quickly and cheaply produce lead hydrate.

In practice l prepare bars or cakes of load hearing are used as anodes bv fusin a 5) lead sulfid ore, preferably in a -r'wcrbcratory hearth in which the atmosphere of the chamber ab re the ore is lie-pt practically reducing by allowing it to remain full of the gaseous products of combustion from the tire box, and then casting or molding the fused ore into bars or cakes in suitable molds of refractory material. .ln practice I find that satisfactory results are obtained when these bars or cakes are in the form of slabs approximately eighteen inches long, twelve inclns wide and two incl cs thick, provided with suitable heads for the positive terminal of the usual electric circuit; it is of course understdi'id that these dimensions may be varied. One or more of such anodes are arranged and supported with their bodies iinmerscdin the liquid'of an electrolytic cell containing a suitable electrolyte prefa'ably a neutral solution of sodium nitrate in water, and provided with one or more of the usual cathodes. lVhen the cell or apparatus is thus equipped and electric current is passed through the anode in any usual manner and by any suitable means nuwwell known in the art. of electrolysis, the. cast lead-bearin ore anode is electrolyzed and the liber v lead is spontaneously precipitated as lead hydate by reaction the water of the bath. The hydrate may b con crtcd into other compo-unds. partic rly lead carbonate or lead oxi'cls, by suitaoie treatment,

Preferably l employ iron wire mesh for Specification of Letters Patent.

Patented Mar. 18, 1913.

Application filed March 2, 1912. Serial No. 681,289.

the cathode. If the anode and'cathode are placed too close together, or if the hydrate produced be allowed to collect on the cathode. considerable metallic lead is produced. By using a low potential, preferably not over four volts, and by placing the anode and cathode approximately three inches apart, the metallic lead is reduced to a negligible quantity. Furthermore, reduction of the hydrate to metallic lead is prevented by placing the cathode in a cloth cell.

By my process all the electricity acts directly upon the cast lead-bearing ore, so that the latter is quickly and cheaply decomposed; and, furthermore, the electrolytic bath is not surcharged with excess of soluble reagents and the same bath can be used for a considerable period, although as the water soluble compounds of the ore and the sulfur therefrom gradually accumulate upon the anode within the bath it may be necessary from time to time to renew the solution or to substitute fresh solution.

A unique feature of my process is that the reagents 6f the bath effect precipitation of the lead hydrate and are regenerated by recombining so that the bath remains unchanged except for the slight loss of water combined in the lead hydrate. This cyclic action etl'ccts economy in consumption of chemicals and is illustrated by the following reactions 2 a l-tcaction (1) illustrates the dissociation of the sodium nitrate and water into sodium hydrate and nitric acid. Reaction shows the decomposition of the lead sultid by the. nitric acid so produced, the. sulfur being deposited and the lead passing into solution as nitrate. Reaction (3) is the decomposition of the nitrate so formed on encountering the sodium hydrate formed in the first reaction with the formation of lead hydrate and the regeneration of sodium nitrate.

\Vith a. potential between one and six volts the current separates some free sulfur. at the anode; this sulfur is not mixed with the hydrate but forms a coating on the anode itself which may be removed by Us and retains the Jclops to such "les oft. @nly is found in out Wholly 21s a J. detrimental and ot the hydrate 7 ng the ore spontaneously V eiroiytic bath or cell.

hose, and

lien on envelop or evoidech and the I :trolytic cell by the reaction of the ingredients of the bath. 7 v

2. The method of producing lead hydrate vwhich consists in electrolyzing e cast anode of lead sulfid ore in 21, neutral hydrous solution of sodium nitrate, and precipitating the hydrate in the electrolytic cell by the reection of the ingredients of the bath.

3.]ihe method of producing lead hydrate which consists in eiectrolyziiig e cast. anode of lead sulfid ore in a neutral hydrous solution of a nitrate by a current of low poten tial, and precipitating the hydrate the electrolytic cell by the reaction of the ingredients of the-hath.

4-. The method of producing teed hydrate which consists in electrolyzing e cast anode of iced sch-id ore in it neutral hydrous solution of sodium nitrate by a current of tow potential anti in the presence of a cathode in a cloth envelop, and precipitating the hydmtein the electrolytic cell by the tion of the ingredients of the he i In testimony whereof efiiiz ture in presence of two Witnesses.

TrIEGD-QEE Witnesses 

